Boring and routing bit



(ModeL) T. D. 000K.

BORING AND ROUTING BIT. No. 340,100. Patented Apr. 20, 1886.

NITED STATES TRUMAN D. COOK, OF TOPEKA, KANSAS.

BORING AND ROUTING BIT.

SPECIFICATION forming part of Letters Patent No. 340,100, dated April 20, 1886. Application filed July 10 1885. Serial X0. 171,236. fhlodel.)

To all whom it may concern.-

Be it known that I, TRUMAN D. 0001;, a citizen of the United States, residing at the city of Topeka, in the county of Shawnee and State of Kansas, have invented a new and useful Improvement in Boring and Routing Bits, of which the following is a specification.

The object of my invention is to furnish a bit to be driven by power that shall perform the functions of an anger, a mortising and tenoning chisel, a rabbeting, chamfering, and channeling plane for straight, curved, or tortuous lines and surfaces, as well as a tool for executing in perfect order and finish the various forms of base and bold relief work. I accomplish this purpose with the device illustrated in the following drawings, in which Figure 1 is an end viewof one of my improved bits having three lips or wings; Fig. 2, a perspective of the same; Fig. 3, an end view of one of my bits having five lips or wings, and Fig. 4 a perspective of the same.

Similar letters indicate similar parts of the device in the several views.

I construct my bit of steel and of any de sired length and circumference. Having determined its length and circumference, I lay out about its axis equidistantly two, three, four, or five, or more, longitudinal lips, a, and dress them into form with a milling-wheel. Each lip is finished up with a cutting-edge, b, along its longitudinal edge, as well as with the cutting-edge c at its end. The under surface of each lip is so curved that any section of it by a plane at right angles to the axis of the bit is a semicircle. The uppersurface of each lip is also curved, this curve being so shaped as that no portion of the surface, save at the line of the cutting-edge I), can come into contact with the material which the bit is cutting. At the same time the furrow d between the several lips is so formed as that it broadens upward from its bed. The longitudinal cutting-edge b is sharpened only at the underside of the lip. The cutting-edge at the end of each lip is formed by a chamfer from the upper side, extending from the circumference of the blt quite to its center, as shown in Figs. 1

and 2. These cutting-edges at the end of the hit all lie in the same plane perpendicular to the axis. In case, however, the bit is not to be employed for boring, the cutting-edges at the end may be constructed for all other work, as is shown in Figs. 3 and 4. Here the end cutting-edges do not extend to the center, but only so far as they will be carried by a plane chamfer in forming them, this chamfer in Figs. 1 and 2 being curved. Again, in Figs. 3 and 4 these end cutting-edges have only the point at the circumference of the bit in the same plane perpendicular to the axis of the bit. Each end cutting-edge recedes slightly and uniformly from this point, dropping away from the said plane, while the circular area within these end cutting-edges recedes still farther from the said plane.

The bit is attached for use to a chuck in the ordinary way at its shank. The material to be cut is firmly secured in place, and the bit is directed at the pleasure of the operator to its work, being thrust forward or moved at right angles to its axis in straight, simple, curved, or tortuous lines, cutting its way and completely finishing the surfaces left in its pathway.

This bit may be driven with perfect safety at a speed of four thousand five hundred revolutions per minute.

XVhat I claim as my invention, and desire to secure by Letters Patent, 1's-- A boring and routing bit constructed with two or more equidistant lateral lips, a, with cutting-edges b, the lips terminating at the working end of the bit in cutting-edges ex tending in the same plane to and meeting at the center or axis of the bit, or extending only to or near to the bases of the lips a, and slightly but uniformly receding toward these bases from the plane of the terminal circumference of the bit, the whole being constructed substantially as and for the purpose hereinbefore described.

' TRUMAN D. COOK. lVi t n esses:

W. H. Pooa, I. T. BIARABLE. 

